Dealing with omitted answers in a survey on social integration of immigrants in Italy

ABSTRACT

Surveys are used to infer the level of social integration of immigrants. Item response theory helps to describe the relationship among responses to test items and latent traits of interest. However, in the presence of nonignorable missing data, which are omitted responses depending on the latent traits to be measured, estimates of the model parameters are biased. To account for nonignorable missing data, the quantity and quality of contacts between immigrants and natives (so called “social integration”) are taken into account through a linear function of the response propensity. Higher education, no intention to migrate again, young age, Albanian nationality, and declaring a non-Muslim religion or none, comparatively favor social integration.     

Generalized Instrumental Variable Models

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海南省恩格尔系数长期偏高的原因及对策

海南省与全国其他地区相比,恩格尔系数长期处于偏高的地位,论题从收入、物价、消费、气候和生活习惯等方面解析了海南恩格尔系数长期偏高的原因,并从提高收入、调整结构以及增加供给等方面提出了对策。     

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空间面板数据模型将空间计量经济学和面板数据方法相结合,不仅同时考虑时空特征,而且将空间效应纳入研究体系,成为当前计量经济学的热点研究领域,但其模型设定、参数估计及模型检验也更为复杂,实证研究中往往出现模型设定偏误等问题。因此,基于空间面板数据模型的前沿理论,重点探讨模型设定中的常见问题,包括空间滞后模型与空间误差模型的选择、随机效应与固定效应的选择以及模型拟合优度的选择与比较,为模型的应用和新模型的扩展提供理论依据和参考。     

高速数字存储示波器产品化设计的关键技术

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困境与出路：对农村计划生育管理中“补锅匠现象”的社会学透视

在农村的计划生育管理中,普遍存在基层干部和计划生育管理者放任甚至希望对象户超生的现象,我们称之为“补锅匠现象”。这一现象产生的原因是多方面的,它不仅损害了党和政府的形象,而且严重破坏了基本国策的执行。要逐步消除这一现象,根本出路在于制度建设。     

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运用哲学层面的环境制约原理、不确定性原理、系统原理探讨差异教学的形成与发展、教学目标、教学内容、教学过程、教学方法、教学活动管理等问题,揭示了差异教学的深刻的哲学渊源,为差异教学理论提供了可靠的哲学依据。